Quantitative determination of toxic metals in soil by laser induced breakdown spectroscopy

摘要

Laser-induced breakdown spectroscopy (LIBS) is a promising technique for in situ environmental analysis. The potential of this technique for accurate quantitative analysis of heavy metals in soil could be greatly improved by optimized the time delay, laser energy, working distance, et. and by analyzing the results with a procedure which overcomes the problem related to the physical character of soil sample. A LIBS system for soil analysis is reported here. The optimum experimental conditions for quantitatively measurement of Sr and other heavy metals in soil are presented. A new data acquisition and statistical method has been used to analyze the recorded spectra. The precision of this method, in terms of relative standard deviation (RSD), is of 7 % for Sr 1 460.73 nm. The calibration curve for quantitative measurement of Sr has been built. From the calibration curves, the detection limits of Sr in soil were determined to be 15.0 μg/g, and are better than the data reported in literature.